Gather your ingredients and tools. Make sure you have a medium saucepan, a large nonstick skillet, a baking dish, and a cutting board.

Rinse and drain the quinoa to remove any bitterness.

Put the rinsed quinoa into a medium-sized saucepan. Pour in the vegetable broth and bring the mixture to a gentle boil over medium-high heat.

Once boiling, reduce the heat to low, cover, and let it simmer for about 15 minutes.

Leave it covered for an additional 5 minutes after removing it from heat, then fluff with a fork.

Preheat your oven to 375°F (190°C). Slice each bell pepper in half lengthwise and carefully remove the seeds and membranes.

Arrange them in a 9x13-inch baking dish, cut side up.

Pour a small amount of water into the bottom of the dish to help the peppers stay moist while baking.

In a large nonstick skillet, heat the olive oil over medium heat. Add the finely chopped onion and sauté until softened and slightly golden, about 2–3 minutes.

Stir in the minced garlic and cook for another 30–60 seconds until fragrant.

Add the cooked quinoa, diced tomatoes (with their juices), black beans, and corn to the skillet with the sautéed onions and garlic. Season with cumin, paprika, salt, and black pepper.

Stir thoroughly to combine everything and cook for about 5 minutes, stirring occasionally, until the mixture thickens slightly.

Carefully scoop the warm quinoa mixture into each prepared bell pepper half using a large spoon, filling them generously.

Sprinkle shredded Monterey Jack cheese over the top of each stuffed pepper.

Place the baking dish uncovered in the preheated oven. Bake for 30–35 minutes, or until the peppers are fork-tender and the cheese is melted and bubbly.

For a slightly golden crust on the cheese, switch the oven to broil for the final 1–2 minutes, keeping a close eye to prevent burning.

Once baked, remove the dish from the oven and allow the stuffed peppers to cool for a few minutes.

Garnish with chopped cilantro, diced avocado, or a dollop of sour cream, and serve warm.